An organic light-emitting diode (OLED) has unique characteristics such as self luminescence, rapid response, a variety of color, wide view angle, and capability of being manufactured on a flexible substrate. A display based on the OLED becomes a mainstream in a display field.
An OLED display backplane includes an array substrate and organic light-emitting devices, and each of the organic light-emitting devices includes an anode, an organic light-emitting layer and a cathode. The array substrate includes a driving circuit formed by using thin film transistors (TFTs). A pixel definition layer (PDL) is made at the array substrate to separate pixel regions from each other, for example, each of the pixel regions is an opening, and each opening is provided with one of the organic light-emitting devices. At present, the requirements for power consumption, efficiency, viewing angle and color cast in the display field is becoming more and more stringent. If the cathode of the organic light-emitting device is thin, the color cast is reduced, and at the same time when the light transmittance of the cathode is increased, the luminescence efficiency of the organic light-emitting device is improved.